RF detector, short for radio-frequency detector, is a device that detects and measures the presence of RF signals in the vicinity. It has two main components: a receiver and a detector which measure the amplitude of any incoming signals and convert them into electrical signals for further analysis. Additionally, some devices also include an indicator that can inform the user of the magnitude of the radio-frequency signals present, allowing for easier and faster discovery of their source. These devices are used to locate and identify radio-frequency interference (RFI) and can be either active or passive. Active RF Detectors contain a scanner that actively searches for incoming radiofrequency signals. Passive detectors, on the other hand, detect currently existing signals without actually searching for them. They are mostly used to reduce interference, usually during broadcasting.